Improvement in combined extension measuring-rods and dividers



G. H. DISGHER. -Combined Extension Measuring-Rods and Dividers.

N0, 144,264, Patente@ Nov.4,1873..

Jig. 2

Witnesses: mamon UNITED STATES PATENT OFFICE.

GEORGE H. DISOHER, OF MOBILE, ALABAMA.

`IMPROVEMENT IN COMBINED EXTENSION MEASURlNG-RODS AND DIVIDERS.

Specification forming part of Letters Patent No. 144,264, dated November 4, 1873 `applicaticm filed August 30, 1878.

To all whom it may concern:

Be it known that I, GEORGE H. DIscHEn, of Mobile, in the county of Mobile and State of Alabama, have invented a new and useful Improvement in Combined Extension-Rod and Tram, of which the following is a specification:

The object of this invention is to facilitate the taking of measurements between rigid surfaces and striking circles, arcs of circles, and ovals and elliptics 5 and it consists in an extension-rod having tram-xtures, constructed and arranged as hereinafter described.

In the accompanying drawing, Figure l is a view showing the three parts of which the rod is composed. Fig. 2 is a side view, showing the tram-points and-pencil. Fig. 3 is a crosssection of Fig. 1 taken on the line w m.

Similar letters of reference indicate corresponding parts.

A is the center piece, in each of two opposite sides of which is a dovetail groove. (Indicated by dotted lines in Fig. l, and seen in full in the cross-section, Fig. 3.) C and D are extension-pieces. Near the inner ends of these extension-pieces are metallic dovetails E E, which fit into and slide in the dovetail grooves of the center piece, and guide and hold those pieces to the center piece. F F are hands attached to the center piece7 which admit the extension-piece, as seen in Fig. l, so that they may slide back and forth therein. G G are thumbscrews in the bands, by which the elitensionpieces are held in any desired position. These extension-pieces are graduated or marked oft' into inches and fractions, so that the length of the rod in feet and inches may be, at any time, readily ascertained. H is a removable point, and I is a removable pencil, each fastened in place by a thumb-screw, J, when the rod is used as a tram for striking circles, arcs of circles, ovals, or elliptics. In the latter case the third point is attached to the end of the center piece.

When not used as a tram, the points and pencil may be disposed of in the ends of the pieces, as indicated in dotted lines.

This is a most useful and convenient instrument for all practical men, and especially for builders and other mechanics.

Having thus described my invention, I claim as new and desire to secure by Letters Pat ent- 1. A combined extension-rod and tra-m, constructed as herein shown and described.

2. The combination of the point and pencil,

arranged in the ends of the extension-pieces C D, with center piece A, for the purposes set forth.

GEORGE HARMAN DISCHER. W'itnesses l JAs. H. HUTcHIssoN, WILLIAM MARCH. 

